Exothermic is a chemical reaction in which heat is released. Lighting a candle is an example of an exothermic because the flame is the heat being released.
Answer:
<h3>no it is not allowed</h3>
Explanation:
<h3>Liwis structure shows the elements symbol with dots thet represents valance electrons ; in second row elements their atomic number is 3 up to 10 , from Li up to Ne from their electron configuration their valance electron will be from 1 up to 8 respectivelly ,if lewis structure represents the element with it is symbol and dots that represents valance electron the second row elements cannot have more than an octet of valance electrons surrounding it.</h3>
<h3>I think it is help ful for you </h3>
Answer:
The molar mass of a compound is The mass in grams of 1 mole of the compound (Option A)
Explanation:
Let's take ammonia as an example (NH3)
Mass of N = 14 g
Mass of H = 1 g
Molar mass of ammonia is Mass of N + (Mass of H).3
14 + 3 = 17 g/m
Ammonia is a compound that has 1 mol of N, plus 3 moles of H (see the formula)
The number of atoms in 1 mole of the compound --> This is Avogadro
Answer:
1)Na2O
let the valency of Na is x
2(x)+(2)=0
2x+2=0
2x=-2
x=-1
2)ZnO
let the valency of Zn is x
x+2=0
x=-2
3)Al2O3
let the valency of Al is x
2(x)+3(2)=0
2x+6=0
2x=-6
x=-3
4)MgO
let the valency of Mg is x
x+2=0
x=-2